Casing perforating device



'Aug. 29, 1939.

P. T. BYNUM CASING PERFORATING DEVICE Filed Aug. 13, 1936 2 Sheets-Sheet 1 Attorneys g 2 1939/ P. T. BYNUM 2,171,442

GAS ING PERFORATING DEVICE Filed Aug. 15, 1956 2 Sheets-Sheet 2 Inventor 4 r 49 45 4a 7%; 7 3 mm By 0 W M Atiorneys Patented Aug. 29, 1939 UNITED STATES PATENT OFFICE CASING PEBFOBATING nnvroa v Pink '1. Bynum, Beeville, Tex. Application August 1:, 1936, Serial No. 95,906

12 Claims.

This invention relates to a device for perforating casings, and more particularly, to fluid actuated perforating tools for use in well casings, tubings, and the like.

5 The general object of. the invention is toprovide a barrel having a large piston therein which actuates the perforating means and 'a second large piston in the barrel located above the flrst piston and having a greater length of stroke than 10 the first piston, with a small cylinder having a small plunger working therein and connected with the second piston and having a passage therein for leading some of the fluid which actuates the second piston into the small cylinder.

Thus the increased pressure produced in the small cylinder by the plunger will act on the first piston to cause the same to force the perforating means against the casing to cause the same to penetrate a casing of considerable thickness.

20 The invention, can be used with either pneumatic means or hydraulic means. When used with compressed air the plunger and the small cylinder will build up an increased pressure to actuate the perforating means by the first-men- 85 tioned piston and when used with hydraulic fluid the longer stroke of the plunger in the small cylinder over the shorter operative stroke of the piston actuating the perforating means will cause the perforating means to penetrate the casing.

Another object of the invention is to-provide means for releasing the fluid pressure above the working pistons to permit a return of the pistons after each perforating operation.

' The invention, together with its objects and advantages, will be best understood from a study of the following description, taken in connection with the accompanying drawings,- wherein:

Figure l is a longitudinal sectional view taken 40 through a perforator providing the features of the present invention with the parts at the very end of the upward reaction, lower valve rods being completely reseated.

Figure 2 is an enlarged detail sectional view through one of the pistons illustrating certain details hereinafter more fully referred to.

Figure 3 is a sectional view taken substantially on the line 3-4 of Figure 1.

Figure 4 is an enlarged detail sectional view through the lower valve-equipped end of the rod of the uppermost piston. I

Figure 5 is an enlarged detail sectional view through a piston head showing an associated u valve in open position.

Figure 6 is a sectional view taken substantially on the line 6-4 of Figure 5.

Figure 7 is an elevationalview of a valve.

Referring more in detail to the drawings, it will beseen that the improved perforator tool or device comprises an elongated cylinder or barrel 5 having threaded in its upper end a plug 6 formed with an internally threaded cylindrical extension 1 to threadedly engage the lower end of a pipe 8 to which is delivered from any suit- 10 able source the fluid for operating the tool.

Secured in the lower end of the cylinder 5 as at 8 is a flanged perforated disk ll through the perforations of which the fluid for actuating the device drains from the cylinder.

Secured in the cylinder I adjacent the upper end thereof as at H is an apertured-disk l2. Spaced downwardly from the disk l2 and suitably secured within the casing 5 is a disk J8 that is disposed below the plane of outlet ports ll provided in the periphery of the cylinder 5.

Also secured within the cylinder 5, as at I5, and spaced downwardly from the disk II, is a perforated apertured disk II, from which rises short supporting rods l1, that support on their upper ends an apertured disk IS.

The disks l2,-l3, II and I0, divide the cylinder 5 into a plurality of chambers Ii, 2|, 2| and 22.

A suitably constructed piston 22 has a working fit within the chamber l8 and is provided with an axially bored stem or plunger 24 that works through the opening in the disk I2 and has a sliding fit within a small cylinder 25, one end of which is threaded within a collar 26 extending upwardly from the disk II. The piston 23 is normally urged upwardly through the medium of a spring 21, and in the lower end of the stem or plunger 24 is an upwardly closing spring pressed ball check valve 2! for a purpose hereinafter made manifest. Spring 21 has its lower end seated on-a sleeve 21 surrounding the cylinder 25 and resting on the collar 28, said spring passes through the opening in the disk l2.

A second piston 2i constructed somewhat simi- 5 larly to the piston 23 has a working fit within the chamber 2| and is secured to oneend of a stem III that works through an opening in the disk l8 and through a centrally located opening in the perforated disk Ii. Disposed about the stem 30 is a spring 3|, as shown. for yleldably urging the piston 28 upwardly.

On the lower end of the stem 3! there is provided a head 32 that has a working flt within the chamber 22 and the head 32 has openings ll, ll

therethrough for a purpose hereinafter made manifest.

The head 32 is also provided with one or more notches 35 that open through the periphery and bottom of the head 32 and accommodate arcuate perforating blades 38 which at one end are pivoted within the notch or notches 35 as at 31.

For guiding the blade 38 outwardly through the opening 38 in the peripheral wall of the casing upon downward movement of the head 32 whereby the blade 38 is caused to pierce and perforate the well casing, there is provided, flxed- 1y within the bottom of the chamber 22 a substantially triangular shaped guide member 38 that is provided at its uppermost angle with a roller 40 against which rides the convex edge of the perforating blade 38.

Each of the pistons 23 and 28 is suitably constructed to provide a plurality of ports 4| therethrough.

For each of the ports 4| there is provided a disk valve 42 secured on an intermediate portion of a valve stem 43. The valve stem 43 works through a suitable guide 44 provided therefor and through the lower end of the piston and at its lower end is equipped with a head 48 against which seats one end of a spring 45 that tends to yieldably engage the disk valve 42 with its seat 4! for closing the passage 4|.

Also, for releasably locking each valve 42 in a raised or open position there is provided for each valve a pair of oppositely disposed spring-pressed balls 48 suitably mounted in the piston and engageable with a groove 48 provided in the .valve stem 43 in a manner clearly shown in Figure 5.

The operation of the device may be briefly described as follows:

In operation, the tool or device is lowered within the well casing the desired depth to reach the point where the well casing is to be perforated or punched. Upon proper positioning of the tool, the-pressure fluid from the source of supply is furnished through the pipe 8. This fluid first enters the chamber l8 and acts to force the piston 23 downwardlv' Certain of the fluid will of course pass through the passage 58 in the plunger 24 and through the valve 28 at the lower end of the plunger into the small cylinder 25. c

The pressure built up in small cylinder 25 by plunger 24 will unseat valve 5| in the bottom of the small cylinder and thus the pressure will pass into chamber 2| to act upon piston 28.

The fluid in the chamber 2| will act on the piston 28 to force the same downwardly, and this in turn will cause the head 32 to move downwardly. As head 32 moves downwardly, the perforating element 38 is caused to move through the opening 38 into engagement with the well casing for puncturing the latter.

As piston 23 approaches the terminus of its down stroke, the head-equipped ends 48 of the valve stems 43 for the valves 42 associated with piston 23 will come into engagement with the disk |2. Such will of course result in an opening of the valves 42 associated with the piston 23 and the valves 42 will become locked in the open position shown in Figure 5.

With the valves 42 associated with the piston 23 in this open position, fluid in the chamber l8 above the piston will flow through the ports 4| in the piston 23 and through the opening in the disk l2 into the chamber 28. Fluid thus within the chamber 20 will drain from the casing 5 through the outlet ports |4.

Similarly, as the piston 28 reaches the limit of its downward stroke, the valve stems 43 associated with the piston 28 will engage the disk |8 resulting in an unseating of the valves 42 associated with piston 28. With the valves 42 of piston 28 in open position, the fluid above the piston 28 will pass through the ports 4| in piston 28 and drain through the opening in the disk l3 and the perforations l8 into the chamber 22.

The fluid thus entering the chamber 22 will flow through the ports 33 and 34 in the head 32 and flnally drain from the cylinder 8 through the perforations in the disk It. It will be apparent that as the fluid pressure above the pistons 23 and 23 is released in the manner Just described, springs 21 and 3| will act on the pistons 23 and 28 respectively to return the pistons to their uppermost positions, thus raising the head 32 for retracting the punch 38 and placing the parts in position to repeat the cycle of operation just described.

Obviously, as the pistons 23 and 28 reach the limit of their return or up stroke, the upper ends of the valve stems 43 will engage the disk 8 and disk |3 respectively, in the manner to release the valve stems and to permit the latter, under the action of the springs 45 to move downwardly, so that the disk valves 42 will re-engage their seats 41. The parts are then in a position shown in Figure 1 and the' next perforating operation is then undertaken.

It will be appreciated that in accordance with the present invention, and through the medium of the valves 42 and the locking means therefor, provision is made for releasing the pressure above the pistons and maintaining the pressure released untilthe pistons have returned to their upper or original position. By such arrangement, the return of the pistons may be accomplished without requiring the complete draining of the casing 5 of the fluid, the return of the pistons being accomplished during the draining of the fluid from the casing.

' As wfll be seen the upper piston 23 with the plunger 24 has 'a much longer stroke than the operative stroke of the lower piston 28 for actuating the perforating means 38 so that the downward movement of plunger 24 is sufficient to displace enough fluid from the cylinder 25 above the piston 28 to cause the piston 23 to operate the tool 38 to cause the tool to perforate the casing.

If compressed air is used for the actuating fluid this air is, of course, introduced into the upper part of the barrel 5 through the pipe 3 so that this air will act. on the upper piston 23 to lower the same and some of this air will pass through the passage 58 in the plunger 24, by the valve 28, into the small cylinder 25. When air is used the parts are arranged so that the plunger- 24 will build up apressure in the cylinder 25 and this increased pressure will act on the lower piston 28 so that this piston 28 as it moves downwardly will cause the tool 38 to engage the casing to perforate the same.

However, I prefer to operate the invention hydraulically by either 011, water or drilling fluid, preferably the latter as this drilling fluid has considerable weight and acts to hold the high gas pressures down. When such drilling fluid is used the valve 5| may be omitted and the plunger 24 acting on this fluid in the cylinder 25 and the increased stroke of the plunger relative to the operative stroke of the piston 28 will cause sufllcient fluid to be displaced from the small cylinder to move the piston 28 downwardly to force the tool 36 against the casing to perforate the same.

The weight of the drilling fluid in the pipe 8 will be equalized before and after each action of the pistons, by the fluid in the well passing through the ports I and through the lower end of this cylinder so that the device will function under the hydrostatic pressure in a deep well.

I find that in some cases the plunger 24 can be made solid and the small cylinder 25 can have its bottom open so that it will communicate directly with the upper end of the chamber 2] in which the piston 29 is located and then the small cylinder and the space above the piston 29 is filled with suitable liquid so that as theupper piston moves downwardly the liquid in the small cylinder II will be forced into the upper end of chamber 2| thus forcing the piston 29 downwardly and then asthe upper piston is raised with the plunger 24 the fluid or liquid will be drawn-back into the small cylinder 28 and the piston 29 will be raised by ltszspring 3!.

Further, it will be found in actual practice, that the tool embodying the features of the present invention may be operated on an ordinary string of pipe or tubing, and that the commonly used drilling pump and hose connections may be employed thus obviating the necessity of installing or using special equipment, which latter would only add tothe cost of the operation of a perforating device.

Having thus described my invention, what is claimed as new is:

1. In a tool of the character described, a cylinder, a piston reciprocatingly movable within the cylinder, a fluid supply means connected with one end of the cylinder to efiect movement of the piston, a punch, means for operatively connecting thepunch with the piston for movement therewith, and said piston having ports extend ng therethrough parallel to the axis of the piston, upwardly opening valves for closing said ports. said valves having stems projecting above and below the piston, means cooperable with said stems for releasably securing-the valves in open position, means in the cylinder below the piston and with which the lower ends of said stems are engageable upon downward movement of the pi ston to move the valves to open position, and means in the cylinder above the piston with which the upper ends of the stems are engageable for releasing the valves, and spring devices engaged with the valve'stems for normally urging the valves to closed position onthe piston.

2. In a tool of the character described. a cylinder, a plurality of vertically spaced disks arranged in the cylinder and dividing the same into a plurality of chambers, including first, second, third and fourth chambers, pistons mounted for reciprocation in the first and third chambers, a valve between the first and third chambers controlled by the movement of the piston in the first chamber, a head mounted for reciprocation in the fourth'chamber, a stem rigidly connecting said head with the piston in the third chamber, a punch attached to said head for movement therewith, fluid supply means connected with said casing, and means for directing the fluid through the successive chambers to effect movement of the pistons and head, each of said pistons having a plurality of ports therethrough, disk valves for closing the upper ends of the ports, stems for said valves having their ends projecting above and below the respective pistons, spring devices connected with said stems for yieldably urging the valves in seated position on said pistons.

3. In a tool of the character described, a cylinder, a partition in the cylinder dividing the same into upper and lower chambers, a piston in each chamber, a head slidably arranged in the lower part of the cylinder below the lower piston, a stem connecting said head with said piston, a punch attached to said head for movement therewith, fluid supply means connected with the upper end of the cylinder for forcing the upper piston downwardly, means between the pistons actuated by the upper piston for increasing the pressure of the fluid and said partition having a port therein for the passage of the said increased pressure to the lower piston to effect movement of said lower piston and the head, each of said pistons having a plurality of ports therethrough, disk valves for closing the upper ends of the ports, stems for said valves having t eir ends projecting above and below the respective pistons, spring devices the valves in seated position on said pistonsQand resilient locking devices mounted onthe respective pistons and engageable with the valve stems for releasably locking the valves in open position and for retaining the valves in open position during the return stroke of the respective pistons.

4. In a tool ofthe character described a barrel, a fluid supply means connected with one end of the barrel, a piston in the barrel, means within the barrel above the piston and responsive to the action of fluid entering'the barrel to force certain of the fluid entering the barrel under pressure against the piston for moving the latter in one direction, means carried by said piston and operable upon the approach of the piston to the extremity of its downstroke for relieving fluid pressure on the piston whereby to permit the latter to move me. return direction or on its upstroke, resilient means connected with the piston and yieldably acting thereon in opposition to the fluid pressure against the piston, and a punch operatively connected with the piston and movable therewith.

5. In a device of the class described, a barrel.

having a partition therein dividing the barrel into upper and lower chambers, a piston in thelower chamber, means for introducing compressed fluid into the upper chamber, and means in the upper chamber and actuated by the fluid for multiplying the pressure of some of the fluid and forcing it into the lower chamber to act upon the piston therein.

6. A well perforating device comprising a barrel, a partition dividing the same into upper and lower chambers, a piston in each chamber, a perforating tool carried by the lower piston, means for introducing fluid into the upper end of the barrel for actuating the piston therein, a small cylinder in the upper chamber having a port connecting the same with the lower chamber, a small plunger depending from the upper piston and working in the small cylinder and having a passage therethrough for introducing some or the fluid into the small cylinder and a downwardly opening check valve in the plunger controlling the passage.

"7. A well perforating device comprising a barrel, a partition dividing the same into upper and lower chambers, a piston in each chamber, a perforating tool carried by the lower piston, means for introducing fluid into the upper end of the barrel for actuating the piston therein, a small cylinder in the upper chamber having a connected with said stems for yieldably urging port connecting the same with the lower chamber, a small plunger depending from the'upper piston and working in the small cylinder and having a passage therethrough for introducin some of the fluid into the small cylinder and a downwardly opening check valve in the plunger controlling the passage, and guiding means for the tool.

8. A well perforating device comprising a barrel, a partition dividing the same into upper and lower chambers, a piston in' each chamber, a perforating tool carried by the lower piston, means for introducing fluid into the upper end of the barrel for actuating the piston therein, a small cylinder in the upper chamber having a port connecting the same with the lower chamber, a small plunger depending from the upper piston and working in the small cylinder and having a passage therethrough for introducing some of the fluid into the small cylinder and a downwardly opening check valve in the plunger controlling the passage, and guiding means for the tool, and said barrel having ports in its sides above the partition and means for relieving the pressure on the upper piston when the piston reaches the lower end of its stroke and spring means for normally holding the pistons in raised position.

9. In a well perforating tool, a barrel, a partition dividing the barrelinto upper and lower chambers, a piston in each chamber, a perforating tool connected with the lower piston, means for introducing fluid into the upper chamber to actuate the piston therein, a small cylinder in the upper chamber and carried by the partition, a

small plunger depending from the upper piston and working in the small cylinderand having a passage therethrough for introducing some of the fluid into the small cylinder, an upwardly closing check valve controlling the passage and the bottom of the small cylinder having a port there'- in communicating the same with the lower cham-' ber, an upwardly closing spring-pressed valve controlling said port, spring means for normally holding the pistons in raised position, means for relieving the pressure on each piston as the same reaches the lower end of its stroke and said barrel having ports therein in communication with the lower part of the upper chamber.

10. In a device of the class described, a barrel, a partition dividing the barrel into upper and lower chambers, a piston in each chamber, a perforating tool actuated from the lower piston, means for introducing fluid into the upper chamber to actuate the piston therein, a small cylinder in the upper chamber and carried by the partition and opening out into the lower chamber, a plunger carried by the upper piston and operating in the small cylinder, the upper piston and the plunger having a much longer stroke than partition and opening out into the lower cham ber, a plunger carried by the upper piston and operating in the small cylinder, said barrel having ports therein communicating the lower end of the upper chamber with the well, a perforating tool actuated by the lower piston, downward movement of the plunger causing the fluid in the small cylinder to enter the lower chamber to cause the lower piston to actuate said tool, a supporting member slidably arranged in the lower chamber below the lower piston and connected with said lower piston, and said perforating tool being pivotally connected with said supporting member, said tool curving downwardly and outwardly and the barrel having an opening therein through which the tool is adapted to pass, the inner edge of the tool being bowed outwardly, and a guiding member in the barrel having a part engaging said edge.

12. In a well perforating tool, a barrel, a partition dividing the barrel into upper and lower chambers, a piston in each chamber, means for introducing fluid into the upper chamber to actuate the piston therein, a small cylinder containing fluid in the upper chamber and carried by the partition and opening out into the lower chamber, a plunger carried by the upper piston and operating in the small cylinder, said barrel having ports therein communicating the lower end of the upper chamber with the well, a perforating tool actuated by the lower piston, downward movement of the plunger causing the fluid in the small cylinder to enter the lower chamber to cause the lower piston to actuate said tool, a supporting member slidably arranged in the lower chamber below the lower piston and connected with said lower piston, and said perforating tool being pivotally connected with said supporting member, said tool curving downwardly and outwardly and the barrel having an opening therein through which thetool is adapted to pass, the inner edge of the tool being bowed outwardly, a guiding member in the barrel having a part engaging said edge, yieldable means for normally holding the two pistons in raised position, valve means carried by the upper piston, and means for opening such valve means when the upper piston nears the end of its downward stroke.

PINK T. BYNUM. 

